SamsungFood (formerly Whisk) has this feature and it's a game changer. Each step allows you to tag ingredients, letting you see the amount (including any scaling changes from adjusting servings) directly within the step as you follow the recipe on your phone—no need to swipe back to the ingredients tab when your hands are dirty.
This is one of the greatest quality-of-life innovations for recipe managers and would be fantastic to have here.
